HOW TO BALANCE PROPELLERS

Four easy steps to increase performance and reduce vibration

- THE MODEL AIRPLANE NEWS CREW

After you build a sport plane, there are a couple things you need to do before you head off to the flying field. For your engine to operate properly, you first have the break it in, and before doing that, it’s important to balance your propeller. Why? Most, if not all, propellers will be out of balance when you buy them. Some will be close to being balanced, others not so much. The advantage of flying with a properly balanced propeller is the elimination of or a great reduction in vibration. Like the wheels on your car, the effects at low rpm are almost unnoticeable, but as the rpm increases so too does vibration. This adds to the wear and tear on your engine’s internal parts and bearings as well as the airplane’s airframe.

In addition, your airplane will have better performance with a smooth-running engine and propeller. With glow engines, less vibration means more of its power is transmitted to the prop to produce more thrust. With electric airplanes, it has a similar effect, and you’ll also get more flight time from your battery packs.

WHAT’S NEEDED

All you need to true up your propellers is a high-quality, precise prop balancer, like the one sold by Du-Bro Products; some sandpaper; some Zap CA glue and kicker; and a prop reamer. We like to use a sanding bar with 100-grit sandpaper as it provides a very smooth surface.

LET’S GET STARTED